Mobile electrical power source

ABSTRACT

A portable power source ( 10 ) includes a housing ( 12 ), a stator component ( 20 ), a rotor component ( 18 ), a crank assembly ( 14 ), and a control system ( 24 ). The stator component ( 20 ) is secured to the housing ( 12 ), the rotor component ( 18 ) rotates relative to the stator component ( 20 ) and the crank assembly ( 14 ) is coupled to the rotor component ( 18 ). The crank assembly ( 14 ) is rotated by the user relative to the housing ( 12 ). As provided herein, rotation of the crank assembly ( 14 ) by the user results in rotation of the rotor component ( 18 ) relative to the stator component ( 20 ). In one embodiment, the control system ( 24 ) controls the amount of torque required to rotate the crank assembly ( 14 ). For example, the amount of torque required to rotate the crank assembly ( 14 ) is varied according to the rotational position of the crank assembly ( 14 ). In one embodiment, the crank assembly ( 14 ) includes a one-way drive mechanism assembly ( 725 ) that allows for unidirection rotation of the rotor component ( 18 ) and pedals ( 708 A) ( 708 B) that move up and down.

CROSS-REFERENCE TO RELATED APPLICATION

This is a divisional application and claims priority on U.S. patentapplication Ser. No. 10/693,600 filed on Oct. 23, 2003, the contents ofwhich are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to manually driven powergenerators.

BACKGROUND

Portable electronic devices are used for a variety of useful functions,including (i) communications devices such as mobile telephones, citizenband radios, family radio spectrum radio, and wireless internet devices,(ii) portable computing devices such as notebook computers, personaldigital assistants, and calculators, (iii) military electronic devices,such as night visions devices, communications devices, precision GPS,laser targeting devices, data displays, and computing devices, and (iv)other items such as digital cameras, camcorders, global positionsatellite devices, portable electronic games, flashlights, radios, andaudio CD/MP3 players. Further, many more such types of devices are beingcreated all the time. In some cases, the new electronic devices havebecome critically important to public safety such as 911 emergencyservice on mobile telephones, or global position satellite devices forgeneral aviation and marine use.

One common element in all these portable electronic devices is theirneed for portable electrical power. This has been traditionally solvedby using assemblies of chemical batteries, either the one time usedisposable batteries (such as alkaline, zinc-air), or the multiple userechargeable batteries (such as nickel-cadmium, nickel-metal-hydride,lead-acid, lithium-ion).

Electronic devices can only be truly portable if their power sources arealways available in the field. Disposable batteries have a finitecapacity. One option is to carry a sufficient supply of spare disposablebatteries. However, each of the electronic devices can have a differentpower requirement with different voltages and currents. As a resultthereof, the user may be required to carry multiple different types ofbatteries. Further, on a long trip or mission, the user may have tocarry multiple sets of backup batteries. Moreover, the used batteriescreate a significant waste problem because they often contain toxicchemicals such as lead or mercury. As a result thereof, in many insituations, it is not practical to carry sufficient spare batteries.

Rechargeable batteries must be near a power source to be recharged,typically, a source of 60 Hz/120V. This is generally not available inremote locations. Alternatively, dynamo style power generators have along history of usage. However, these generators are bulky, lowpower,single voltage, single device, hard to crank, inefficient, no feedback,and/or dangerous to batteries.

In light of the above, there is the need for an efficient portabledevice to produce electrical energy in the field. Additionally, there isa need for a power source that can be used to generate output currentand voltages to a wide range of different electronic devices with theirvarious battery chemistries and power needs. Moreover, there is a needfor a power source that is relatively easy and efficient to use andcontrol. Further, there is a need for a power source that reduces userfatigue.

SUMMARY

The present invention is directed to power source that is powered by auser. The power source includes a housing, a stator component, a rotorcomponent, a crank assembly, and a control system. The stator componentis secured to the housing, the rotor component rotates relative to thestator component and the crank assembly is coupled to the rotorcomponent. The crank assembly includes a crank output that is rotated bythe user relative to the housing. As provided herein, rotation of thecrank assembly by the user results in rotation of the rotor componentrelative to the stator component.

In one embodiment, the crank assembly includes a one-way drive mechanismthat couples the crank assembly to the rotor component. The one-waydrive mechanism inhibits rotation of the crank output relative to therotor input when the crank output is rotated in a first rotationaldirection and allows for rotation of the crank output relative to therotor input when the crank output is rotated in a second rotationaldirection that is opposite from the first rotational direction.

In one embodiment, the control system controls the amount of torquerequired to rotate the crank assembly. For example, the amount of torquerequired to rotate the crank is varied according to the rotationalposition of the crank. More specifically, when the crank assembly at afirst rotational position the crank torque is different than when thecrank assembly is at a second rotational position. In alternativeembodiments, (i) when the crank assembly is at a first rotationalposition, the crank torque is at least approximately 2 percent greaterthan when the crank assembly is at a second rotational position, (ii)when the crank assembly is at a first rotational position the cranktorque is at least approximately 5 percent greater than when the crankassembly is at a second rotational position, (iii) when the crankassembly is at a first rotational position the crank torque is at leastapproximately 10 percent greater than when the crank assembly is at asecond rotational position, or (iv) when the crank assembly is at afirst rotational position the crank torque is at least approximately 50percent greater than when the crank assembly is at a second rotationalposition. In addition, the overall drag level can be set via usercontrol so that a weaker person can select a lighter setting than a verystrong person. In this fashion, drag levels can span a typical range of200 to 500 percent from minimum to maximum level.

As provided herein, the crank torque decreases as the angular velocitydecreases and the crank torque increases as the angular velocityincreases. This torque versus speed relationship can be completelyspecified with the electronics as described below.

The power source can be manually driven. In one embodiment, the powersource enables charging of electronic devices in the field whilecontrolling the output voltage and current and maintaining constantinput torque drag.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of this invention, as well as the invention itself,both as to its structure and its operation, will be best understood fromthe accompanying drawings, taken in conjunction with the accompanyingdescription, in which similar reference characters refer to similarparts, and in which:

FIG. 1A is a perspective view of a first embodiment of a power sourcehaving features of the present invention and an electronic device;

FIG. 1B is a partially exploded, first perspective view of the powersource of FIG. 1A;

FIG. 1C is a partially exploded, second perspective view of the powersource of FIG. 1B;

FIG. 1D is a cross-sectional view taken on line 1D-1D in FIG. 1A;

FIG. 2A is a top view of a stator component and a rotor component havingfeatures of the present invention;

FIG. 2B is a top view of another embodiment of a stator component and arotor component having features of the present invention;

FIG. 2C is a cut-away view taken on line 2C-2C in FIG. 2A;

FIG. 2D is a cut-away view taken on line 2D-2D in FIG. 2B;

FIG. 2E is a perspective view of one embodiment of a magnet array havingfeatures of the present invention;

FIG. 3A is a diagram of a flyback converter having features of thepresent invention;

FIG. 3B is a diagram of a switching converter having features of thepresent invention;

FIG. 3C is a diagram of a microprocessor controller having features ofthe present invention;

FIG. 3D is a buck stage followed by a SEPIC stage and microprocessorhaving features of the present invention;

FIG. 3E is a firmware flowchart having features of the presentinvention;

FIG. 3F is a simplified illustration of a power source having featuresof the present invention;

FIG. 3G is a graph that illustrates drag torque versus arm angle foranother embodiment of the power source at a constant RPM;

FIG. 3H is a graph that illustrates drag torque versus arm angle for oneembodiment of the power source;

FIG. 31 is a graph that illustrates a variety of possible duty cycleversus rotor/crank arm speed curves;

FIG. 4 is a view of another embodiment of a power source having featuresof the present invention;

FIG. 5A is a perspective view of still another embodiment of a powersource in a portable position, having features of the present invention;

FIG. 5B is a perspective view of the power source of FIG. 5A in a useposition, having features of the present invention;

FIG. 5C is a perspective view of yet another embodiment of a powersource having features of the present invention;

FIG. 6A is a perspective view of first embodiment of a power sourcecombination having features of the present invention;

FIG. 6B is a perspective view of second embodiment of a power sourcecombination having features of the present invention;

FIG. 6C is a perspective view of third embodiment of a power sourcecombination having features of the present invention;

FIG. 7A is a perspective view of another embodiment of a power sourcehaving features of the present invention;

FIG. 7B is a partly exploded perspective view of the power source ofFIG. 7A;

FIG. 7C is an exploded perspective view of a portion of the power sourceof FIG. 7A;

FIG. 7D is another exploded perspective view of a portion of the powersource of FIG. 7A;

FIG. 7E is another exploded perspective view of a portion of the powersource of FIG. 7A;

FIG. 7F is a perspective view of a one-way drive mechanism of the powersource of FIG. 7A;

FIG. 8A is a graph that illustrates capacitive and inductive current forone embodiment of a power source;

FIG. 8B is an electrical diagram;

FIG. 8C is a graph that illustrates shaft torque profile for oneembodiment of a power source;

FIG. 8D is a graph that illustrates current, voltage waveforms inbipolar operation of a single phase bridge rectifier with pulse widthmodulation;

FIG. 8E is a graph that illustrates shaft torque profile for anotherembodiment of a power source;

FIG. 9A is a diagram that illustrates one embodiment of an internalshunt that creates input shaft drag;

FIG. 9B is a diagram that illustrates an alternative embodiment of aninternal shunt for one embodiment that creates input shaft drag; and

FIG. 9C is a diagram that illustrates yet another embodiment of aninternal shunt for one embodiment that creates input shaft drag.

DESCRIPTION

FIG. 1A is a perspective view of a first embodiment of a power source 10and an electronic device 11 or object that can be charged with the powersource 10. The power source 10 can be used as a manually driven, mobileand portable generator. For example, the power source 10 can weigh lessthan approximately 0.2 pounds, 0.5 pounds, 1 pounds, 2 pounds, 3 pounds,5 pounds, 10 pounds, or 20 pounds. Alternatively, for example, the powersource 10 can be designed as a stationary generator 10.

The type of electronic device 11 charged by the power source 10 canvary. For example, the electronic device 11 can be portable and caninclude (i) communications devices such as mobile telephones, citizenband radios, family radio spectrum radio, and wireless internet devices,(ii) portable computing devices such as notebook computers, personaldigital assistants, and calculators, (iii) military electronic devices,such as night visions devices, communications devices, precision GPS,laser targeting devices, data displays, and computing devices, and (iv)other items such as digital cameras, camcorders, global positionsatellite devices, portable electronic games, flashlights, radios, andaudio CD/MP3 players. Alternatively, the electronic device can bestationary.

The electronic device 11 can be, or include a battery pack 11A(illustrated in phantom) having one or more rechargeable batteries. Asprovided herein, the power source 10 can be used with batteries packs11A having different charging requirements, such as different voltagerequirements and/or different current requirements.

In the embodiment illustrated in FIG. 1A, the power source 10 can beoperated independently of the particular electronic device 11 beingcharged.

FIGS. 1B and 1C are partially exploded perspective views of the powersource 10 of FIG. 1A. One or more of the features provided herein can beused in BLDC generators and/or SR generators. As illustrated in FIGS. 1Band 1C, the power source 10 can include (i) a housing 12, (ii) a crankassembly 14, (iii) a gear assembly 16, (iv) a rotor component 18, (v) astator component 20, (vi) a bearing assembly 22, and (vii) a controlsystem 24. The design of each of these components can be varied to suitthe design requirements of the power source 10.

The housing 12 supports the components of the power source 10. The sizeand shape of the housing 12 can be varied to suit the designrequirements of the power source 10. For example, the housing 12illustrated in FIGS. 1B and 1C includes a first housing segment 26, asecond housing segment 28, and a third housing segment 30. The firsthousing segment 26 includes a substantially planar region 26A having anouter surface and an inner surface, and a tubular region 26B thatextends substantially perpendicularly away from the inner surface of theplanar region 26A near a periphery of the planar region 26A. The planarregion 26A further includes a raised section 26C near the end of thehousing 12 away from the control system 24. The raised section 26C isstepped up away from the outer surface of the planar region 26A so thatthe outer surface of the raised section 26C is substantially parallel tothe outer surface of the planar region 26A. The raised section 26Csubstantially surrounds a portion of the gear assembly 16. Near thecenter of the raised section 26C is a small pivot aperture (not shown)that receives a portion of the crank assembly 14. The bearing assembly22 includes a bearing (not shown) that secures the crank assembly 14 tothe housing 12 and allows the crank assembly 14 to rotate.

The second housing segment 28 is somewhat planar and rectangular shaped,and is positioned spaced apart from and substantially parallel to thefirst housing segment 26. The second housing segment 28 includes anaperture 34 that is substantially circular and is positioned to receivea portion of the third housing segment 30.

The third housing segment 30 includes a generator region 36 and acontrol region 38. The generator region 36 includes a generator cavity40 that can be positioned at an end of the generator region 36 near thecontrol region 38. The generator cavity 40 is sized and shaped toreceive the rotor component 18, the stator component 20, and a portionof the bearing assembly 22. At an end of the generator region 36 awayfrom the control region 38, the third housing segment 30 includes acrescent shaped cavity 42. The generator region 36 extends substantiallyperpendicularly between the first housing segment 26 and the secondhousing segment 28 near a periphery of the second housing segment 28,and is secured to the first housing segment 26 and the second housingsegment 28. The generator region 36 has somewhat the same size and shapeas the first housing segment 26, so that the periphery of the firsthousing segment 26 substantially matches the periphery of the generatorregion 36.

The control region 38 is substantially rectangular shaped with a cavity44 that is sized and shaped to receive the control system 24 and abattery pack 46. The control region 38 extends substantiallyperpendicularly away from the second housing segment 26 and is securedto the second housing segment 28.

The first housing segment 26, the second housing segment 28 and thethird housing segment 30 cooperate to substantially surround the otherelements of the power source 10 exclusive of the crank assembly 14.

The first housing segment 26, the second housing segment 28 and thethird housing segment 30 can be made of a suitable, rigid material.Suitable materials include aluminum, ABS plastic, and/or steel.

The crank assembly 14, when operated by a user, causes the resultingclockwise or counterclockwise rotation of the gear assembly 16. Powersource 10 will work in both directions, while power source 510 shown inFIG. 5B would work best with a single direction rotation. In FIGS. 1Band 1C, the crank assembly 14 includes a pivot assembly 48 having a disccomponent 50 and the rod component 52, an arm 54, and a handle 56 havinga handle knob and a handle pin. The disc component 50 has asubstantially circular cross-section with a flat upper surface and aflat lower surface, and is positioned spaced apart from the outersurface of the raised section 26C of the first housing segment 26. Thedisc component 50 further includes a disc aperture that receives the rodcomponent 52. The rod component 52 is a slender rod with a substantiallycircular cross-section that extends into the disc aperture and issecured to the disc component 50. The rod component 52 secures the disccomponent 50 to the gear assembly 16.

The arm 54, as illustrated in FIGS. 1B and 1C, has a proximal end and adistal end. The proximal end has an arced cutout that receives the disccomponent 50 of the pivot assembly 48. The proximal end also includesapertures near either end of the arced cutout that receive small pins 58that extend through the apertures and into the disc component 50 tosecure the arm 54 to the disc component 50. The arm 54 extends away fromthe pivot assembly 48 substantially parallel to and spaced apart fromthe outer surface of the first housing segment 26. Near the distal end,the arm 54 can also include a handle aperture that receives the handlepin and secures the handle 56 to the arm 54. Alternatively, the handle56 can be designed without the handle pin wherein the handle knob issecured to the arm 54 with an adhesive or another type of fastener.

As noted above, the handle 56 can include the handle knob and the handlepin. The handle knob is shaped so that it can easily be gripped by theuser and operator of the crank assembly 14. The handle 56 is designed sothat it can easily be gripped with either the left hand or the righthand of the user for the convenience of the user. The arm 54 rotatesabout the pivot assembly 48 when the user applies a force to the handle56 in a direction substantially perpendicular to the arm 54 andsubstantially parallel to the outer surface of the first housing segment26. The power source 10 is designed so that the arm 54 can rotate aboutthe pivot assembly 48 in a clockwise or a counterclockwise (when lookdown at the first housing segment 26) direction to generate power. Theparticular direction of rotation of the arm 54 about the pivot assembly48 depends on the ease and convenience of the user.

The gear assembly 16 mechanically couples the crank assembly 14 to therotor component 18. The gear assembly 16 can have a gear ratio of theinput to output of 1:1, greater than 1:1, or less than 1:1. For example,with the design provided herein, the gear assembly 16 can have a gearratio of between approximately 3:1 and 16:1. For example, in alternateembodiments, the gear assembly 16 can have a gear ratio of approximately4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, or up to25:1. The power source 10 provided herein is a high energy densitygenerator that allows for the use of a lower gear ratio, thereforeresulting in lower stresses and wear on the mechanical elements such asgear teeth and bearing assembly 22. This benefit further results inlower cost and longer system life.

The rod component 52 of the crank assembly 14 extends through the raisedregion 26C of the first housing segment 26 and is secured to the gearassembly 16. In FIG. 1B, the gear assembly 16 includes a first gear 60,a second gear 62 and a third gear 64. The first gear 60 is secured withthe rod component 52 to the disc component 50. The first gear 60 ispositioned substantially parallel to and spaced apart from the innersurface of the raised section 26C of the first housing segment 26. Asthe user inputs a force to the handle 56 of the crank assembly 14, thearm 54 of the crank assembly 14 rotates about the pivot assembly 48. Asthe arm 54 rotates about the pivot assembly 48, the pivot assembly 48and, more specifically, the rod component 52 also rotates. The rotationof the rod component 52 further causes the first gear 60 to rotate. Thefirst gear 60 is enmeshed with the second gear 62 so that the rotationof the first gear 60 causes the second gear 62 to rotate in the oppositedirection. The second gear 62 is enmeshed with the third gear 64 so thatthe rotation of the second gear 62, in turn, causes rotation of thethird gear 64. The third gear 64 is secured to the rotor component 18.As a result thereof, rotation of the third gear 64 results in rotationof the rotor component 18.

Alternatively, the power source 10 can be designed so that the crankassembly 14 directly drives the rotor component 18. In this embodiment,the power source 10 does not include the gear assembly 16. Stillalternatively, the gear assembly 16 can include more than three or lessthan three gears.

The rotor component 18 and the stator component 20 cooperate to convertmechanical energy from the rotation of the crank assembly 14 toelectrical energy. In FIGS. 1B and 1C, the rotor component 18 issomewhat disk shaped and includes a pair of rotor pins 66 that extendalong the central axis of the rotor component 18 from either end of therotor component 18. The rotor pins 66 are spaced apart from each other,essentially forming a discontinued line along the central axis of therotor component 18. The rotor component 18 rotates about the rotor pins66.

The stator component 20 is substantially ring shaped and substantiallyencircles the rotor component 18. The stator component 20 furtherincludes at least one bump 68 along an outer edge that fits into atleast one indentation 70 along the outer edge of the generator cavity40. As shown in FIGS. 1B and 1C, the stator component 20 can include twobumps 68 that interact and fit into two indentations 70 in the generatorcavity 40 to inhibit rotation of the stator component 20. Alternatively,the stator component 20 can include more than two or less than two bumps68, and the generator cavity 40 can include more than two or less thantwo indentations 70. Also alternatively, the stator component 20 caninclude one or more indentations 70 that coincide with one or more bumps68 in the generator cavity. Still alternately, the stator component 20can be secured to the housing 12 in another fashion.

In an alternative embodiment of the present invention, the positions ofthe rotor component 18 and the stator component 20 can be reversed sothat the rotor component 18 is substantially ring shaped andsubstantially encircles the stator component 20.

As provided herein, one of the rotor component 18 and the statorcomponent 20 includes a magnet array 72 having one or more magnets andthe other of the stator component 20 and the rotor component 18 includesone or more turns of wire 74. The multiple turns of wire 74 can be madeof copper or another electrically conductive material that is embeddedin an epoxy or another type of adhesive, the purpose of which is toreduce acoustic noise and improve thermal heat dissipation.

In FIGS. 1B and 1C, the stator component 20 includes the multiple turnsof wire 74, and the rotor component 18 includes the magnet array 72.Alternately, the power source 10 may be designed so that the statorcomponent 20 includes the magnet array 72 and the rotor component 18includes the multiple turns of wire 74.

The bearing assembly 22 supports the rotor component 18 and the gearassembly 16 relative to the housing 12 and allows the rotor component 18and gear assembly 16 to rotate relative to the housing 12. In FIGS. 1Band 1C, the bearing assembly 22 includes multiple, spaced apart bearings80.

The control system 24 controls charging of the electronic device 11(illustrated in FIG. 1A). In one embodiment, the control system 24controls the torque at the crank assembly 14 that is experienced by theuser. In one embodiment, the control system 24 constantly monitors theinput and output parameters of the power source 10 and provides visualfeedback to the user as to the progress of the power generation process.Depending upon the embodiment, the control system 24 can perform one ormore of the features of (i) adjusting the torque experienced by the userduring rotation of the crank assembly 14, (ii) automatic detection ofthe load voltage required to charge the electronic device 11, (iii)allow for the hookup of multiple power sources 10 to charge theelectronic device 11, (iv) detect and configure to charge various custombattery types, (v) dynamically adjust the output voltage, (vi)dynamically adjust the output current, and/or (vii) dynamically maintaina rotational velocity of the rotor component.

In one embodiment, the control system 24 includes a display 80, a userinput 82 and a control board 84 (illustrated in phantom). The display 80can display one or more of the functions of the power source 10. Forexample, the display 80 can display one or more of the features (i) therate of charging of the electronic device, e.g. somewhat similar to agas gage for a car, (ii) the estimated additional time required tocharge the electronic device, (iii) the battery type of the electronicdevice being charged, (iv) voltage, amps, watts being delivered to thedevice/battery, (v) minutes of device usage stored such as talktime on acellphone, (vi) battery temperature, state-of-health, (vii) movinggraphic to help user maintain optimum cranking pace and/or (viii) thatthe device is fully charged.

In one embodiment, the display 80 is a liquid crystal display.Alternatively, for example, the display 80 can include one or more gagesor other type of monitors such as LEDs.

The user input 82 allows the user to communicate instructions to thecontrol board 84 as well as to the display 80. For example, the userinput 84 allows the user to specify the required charging conditions andtermination conditions by specifying particular voltages, output power,etc., or by selecting among several previously defined battery types orelectronic devices (ex: cellphone types). Further, the user input 82 canallow the user to adjust desired crank torque drag up or down for theconvenience of the individual user.

In the embodiment illustrated in FIG. 1C, the user input 82 includes aplurality of buttons 86 that are electrically connected to the controlboard 84. The user can depress and/or move the buttons 86 to giveinstructions to the control board 84. Alternatively, for example, theuser input 82 can include one or more knobs or the user input 82 can bevoice activated.

The control board 84 acts as the central component of the power source10, coordinating all monitoring, control, and status display functions.Further, the control board 84 can perform the functions of the controlsystem 24 described above. In one embodiment, the control board 84firstly accepts the input from the user with the user input 82specifying the target battery charging requirements of voltage andcurrent, and termination conditions of voltage, NDV or temperature forthe electronic device 11. This feature allows the power source 10 toaccommodate many different voltages, currents, etc. of the many types ofbattery chemistries. Additionally, commands such as desired crank dragare specified here. The functions of the control board 84 are describedin more detail below.

In one embodiment, the power source 10 includes the internal batterypack 46. This allows for more rapid human energy input than many smallportable devices can accept. Additionally, the internal battery pack 46can accommodate more rapidly fluctuating voltages and currents thanwould be tolerated by many electronic devices 11. The power source 10can also include a bypass circuit so that even if the internal batterypack 46 is dead, the power source 10 can still charge the electronicdevice 11. As provided herein, the battery pack 46 can include one ormore rechargeable batteries 88, such as nickel-cadmium,nickel-metal-hydride, lead-acid, and/or lithium-ion.

FIG. 1D is a cut-away view of the power source 10. FIG. 1D illustratesthat the rotor component 18 and the stator component 20 are concentricto each other. The rotor component 18 rotates about a central axis 90while the stator component 20 remains stationary. Equivalently, theorder could be reversed with the rotor spinning external to the stator.

FIG. 2A is a top view of a stator component 220A and a rotor component218A that can be used in the power source 10 of FIG. 1A. In thisembodiment, the rotor component 218A includes 10 poles 200A and thestator component 220A includes 15 slots 202A. Thus, the slot/pole ratiois 15/10. Stated another way, the pole/slot ratio has a common factor.For 3 phase generators, the number of slots and the number of poleshaving a common factor can be wound with a simple ABCABC . . . patternwhere A,B,C refer to the 3 winding phases, and uppercase letters refersto winding coils clockwise around each tooth shank. A lower case letterindicates winding a coil counter-clockwise around each tooth shank.Other examples of slot/pole ratios include 9slot/12pole, 9slot/6pole,and 6slot/8pole. These examples have the virtue of an obvious windingpattern—ABCABC . . . with all teeth wound clockwise, and each 3^(rd)tooth belonging to the same phase. However, common factor pole/slotratio generators can have relatively high cogging torques.

FIG. 2B is a top view of another embodiment of the stator component 220Band the rotor component 218B that can be used in the power source 10 ofFIG. 1A. In this embodiment, the rotor component 218B includes 16 poles200B and the stator component 220B includes 15 slots 202B. Thus, theslot/pole ratio is 15/16. Further, the least common multiple of thisdesign is 240. Stated another way, the pole/slot ratio does not have acommon factor that evenly divides into the number of poles or slots andthe power source has a fractional pole/slot ratio. In this embodiment,the winding pattern can be AaAaABbBbBCcCcC where the uppercase lettersrefers to winding coils clockwise around each tooth shank and the lowercase letters indicate winding a coil counter-clockwise.

Alternatively, the stator component 220B and the rotor component 218Bcan be designed with fractional pole slot ratios, such as 15slot/14pole,9slot/8pole, 9slot/10pole, 21slot/18pole, or 21slot/20pole. Theseexamples have a least common multiple of 210, 72, 90, 378, or 420respectively.

The fractional pole/slot ratio designs can have a smaller coggingtorques than common factor pole/slot ratio designs. Additionally, thelack of a common factor and a relatively high least common multiplereduces the magnitude and increases the frequency of the cogging cycles.This results in very smooth motion and rotation of the crank assembly.

Further, the stator component 220B and the rotor component 218Billustrated in FIG. 2B have a pole/slot ratio that is very close to 1.Higher strength generators occur when the pole/slot ratios are closestto 1, because this maximizes rotor/stator magnetic coupling. Examples ofsuitable alternative pole/slot ratios have a value of approximately 0.7;0.8; 0.9; 1; 1.1; 1.2; and 1.3.

As provided herein, high vibration and low generator strength can beavoided by using pole/slot ratios with no common factors, and havingpole/slot ratios close to 1. Further, these features can inhibit“cogging”, e.g. relatively large uncomfortable torque vibrations to theuser when cranking that can also cause high acoustic noise.

FIG. 2C is a cut-away view of the stator component 220A and the rotorcomponent 218A of FIG. 2A. FIG. 2C illustrates that the outercircumference of the rotor component 218A is spaced apart from the innerperimeter of the stator component 220A by a radial component gap 204Athat is filled with air. In this embodiment, the radial component gap204A is substantially constant.

FIG. 2D is a cut-away view of the stator component 220B and the rotorcomponent 218B of FIG. 2B. FIG. 2D illustrates that the outercircumference of the rotor component 218B is spaced apart from the innerperimeter of the stator component 220B by a radial component gap 204Bthat is filled with air. In this embodiment, the component gap 204Bvaries around the circumference of the rotor component 218B. Forexample, in this embodiment, the profile of the tooth head 206 of thestator component 220B adjacent to the rotor component 218B is such thatthe radial component gap 204B is smallest at the center of each tooth206 and widest near the edges of each tooth.

As an example, the component gap 204B can vary approximately 5%, 10%,20%, 30%, or 50%. Stated another way, in alternative embodiments, theradial component gap 204B can have (i) a minimum component gap at thetooth center of approximately 0.2 mm and a maximum component gap at thetooth edges of approximately 0.35; (ii) a minimum component gap at thetooth center of approximately 0.5 mm and a maximum component gap at thetooth edges of approximately 0.8 mm; (iii) a minimum component gap atthe tooth center of approximately 0.15 mm and a maximum component gap atthe tooth edges of approximately 0.25 mm; or (iv) a minimum componentgap at the tooth center of approximately 1.0 mm and a maximum componentgap at the tooth edges of approximately 1.5 mm.

In this embodiment, the distal end of each tooth forms a somewhatcurved, e.g. convex surface.

As provided herein, by varying the airgap between the rotor component218B and stator component 220B, the amount of cogging experienced by theuser for a particular rotor and stator design is reduced.

An additional design feature available for both BLDC generators and SRgenerators is to include a stator airgap to be both radial and axial.This can be accomplished with partially interdigitated lam and rotorcomponent iron throughout the z-height, or only on the top and bottomends In another embodiment, the stator component and the rotor componentcan create higher frequency magnetic fluctuation by notching. Thiscauses faster cycle speeds that result in higher generated energy. Insome cases, this may allow the gear assembly to be eliminated entirelyindependent of whether a BLDC generator or a SR generator is being used.

FIG. 2E is a perspective view of one embodiment of a magnet array 272that can be used in the rotor component. In this embodiment, the magnetarray 272 includes a single multiply magnetized permanent magnetconstructed to form alternating north and south poles. The magnet array272 can use high energy sintered NdBFe with strengths of betweenapproximately 40-50 MGOe. Alternatively, the magnet array 272 can havestrengths of between approximately 30-60 MGOe, 30-50 MGOe, or 40-60MGOe. This very strong magnet material allows the power source 10 to bevery compact in size, but requires special features to accomplishmaximum electrical output in minimum physical volume.

In FIG. 2E, the single-piece cylindrical magnet ring magnet array 272 ismagnetized so that the transition 280 between adjacent north poles (N)and south poles (S) is skewed. Stated another way, the magnet array 272is centered about a magnet axis 282 and the transition 280 is at anangle 284 relative to the magnet axis 282. For example, the angle can atleast approximately 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60degrees.

In an alternate embodiment, the magnet array can include multiplediscrete magnets that are secured together into an annular shaped ring.

Additionally, the magnet array 272 can have unique dimensions where theoutside diameter 276 is much larger than the height 278 of the magnetarray 272. In alternative embodiments, the magnet array 22 has a ratioof outside diameter 276 to height 278 of at least approximately 2.5:1,3:1, 4:1 or 5:1.

With the internal rotor component 18, this relationship can accommodateshaft bearings whose z-height is below the lam stack height. This is incontrast to generators that are typically 2:1 with shaft bearings aboveand below the stator lams reducing this ratio to 1:1 or less.

Referring back to FIG. 2B, rotation of the rotor component 218B causesthe magnetic fields created by the magnet poles of the rotor component218B to pass through the multiple turns of wire of the stator component220B. The passage of the wire through the magnetic field created by themagnet poles of the magnet array 272 causes a fluctuating magnetic fluxto pass through the stator component 218B, which induces fluctuatingvoltages in the multiple turns of stator wire according to Faraday'sLaw. The magnitude of and frequency of the induced phases' fluctuatingvoltages depends on the strength of the flux and frequency of passagethrough the magnet poles. Higher pole strengths and faster passage ofthe multiple turns of wire through the alternating north and south polesproduces proportionally higher generated voltages and higher possibleelectrical energy production.

For a generator the efficiency (η) of governed by the followingformulas: $\eta = \frac{Z}{1 + Z}$$P = {{Km}^{2}G^{2}W^{2}\frac{Z}{\left( {1 + Z} \right)^{2}}}$

Where P is power out [watt], Z is load/generator impedance ratio, W ishandle speed [rad/s], G is the gear ratio, and Km is the motor constant[V−S/{square root}Ω].

FIG. 3I illustrates a variety of possible duty cycle versus rotor/crankarm speed curves. In one embodiment, a constant duty cycle could beimplemented. This is illustrated as straight line 357 in FIG. 3I. With asingle-stage flyback converter, this would result in a crank torque thatgets harder as the crank arm is turned faster. The user could select adifferent similar duty cycle curve. This is illustrated as straight line359 in FIG. 3I. In this case, a similar profile of the crank torquewhich gets harder at higher speeds would be obtained. But the overalllevels at all speeds would be harder. This is similar to selecting ahigher bicycle gear ratio. The curved profile 361 of FIG. 3I illustratethat any shape curve can be implemented offering better ergonomics thana single constant duty cycle. In a similar fashion, another similarcurve 363 could be user-selected offering a higher overall level ofeffort. It is to be understood that more than just 2 curves per familycould be easily implemented and selected by the user.

The present invention utilizes a relatively low gear ratio (G) and arelatively high motor constant (Km). As provided herein, the powersource 10 has a motor constant (Km) of at least approximately 50e-3,70e-3, 100e-3, or 200e-3 [V−S/sqrt(ohm)].

In one embodiment, the control board 84 (illustrated in FIG. 1C)includes a first data path, a second data path, a third data path, afourth data path, a plurality of sensors, a first converter and a secondconverter.

In one embodiment, the first converter rectifies the AC phase voltagesto a positive voltage, e.g. DC. This can be accomplished through use ofa simple diode bridge used for BLDCMs, or an actively driven andswitched transistor array used for SRMs. The fluctuating, rectifiedvoltage is a direct and unavoidable result of the varying crank speedproduced by the user. While the human input energy produces fluctuatingvoltage, the target batteries to be charged typically require preciseconstant voltage. Stated another way, the second converter allows thegenerator to dynamically adjust the output voltage, the level ofelectrical energy delivered to the load, and/or the output current todynamically adjust the torque required to rotate the crank assembly 14.

In one embodiment, the second converter is a switching DC-to-DCconverter that can convert an input DC voltage to an output DC voltageby varying the duty cycle of a pulse train (a pulse width modulator orPWM). The second converter helps enable the generator to directly chargethe electronic device at any required voltage or current levels.

One example of a suitable second converter is a Buck-Boost-typeconverter that can be used to produce output voltage equal to negativeD/(1−D) times the input voltage. D is the duty cycle of the PWM switch,which would be 0.25 if the switch were on for ¼ the time and off for{fraction (3/4)} of the time. This feature can be taken advantage of sothat if the human input voltage varies, the duty cycle D of the PWM canbe varied and still produce any constant or varying output voltage aboveor below the input voltage that is desired to drive the target batteryload voltage.

A non-dual stage analog convertor is also possible. FIG. 3A illustratesan example of a single stage flyback convertor. It displays severaluseful properties as already discussed. It converts voltage according tonD/(1−D), where n is the transformer turns ratio. It is capable ofdelivering power to a load that may be above or below the inputgenerator voltage. When driven with a constant duty cycle PWM waveformas in FIG. 3B, it has the desirable characteristics that more currentwill be driven if the crank assembly is turned faster, and less currentwill be driven as the crank assembly is turned slower. This means thatfaster cranking will increase the torque, while slower cranking willreduce it, just as desired for comfort. With this design, even at slowcranking speeds, the battery will still be charging and directly drivinginto a battery. This contrasts with simple diode bridge rectifiers whichonly charge loads when the input crank speeds are high enough togenerate a voltage above the battery load voltage. The PWM wave formillustrated in FIG. 3B is at constant frequency, but need not be.

In an alternative embodiment, a full-wave rectification technique isutilized. With this design, charging stops when the power source isturned too slowly to produce voltage higher than the battery stack.

Additionally, the effort required at any crank assembly rotational speedcan be increased by changing the duty cycle to the convertor asillustrated in FIG. 3B. At a higher duty cycle, the torque will increaseor decrease according to crank assembly speed, as before. But theoverall levels will be higher than before. This enables torque controlsomewhat similar to changing gears on a bicycle. Furthermore, finetuning the PWM duty cycle as the crank assembly is turned through its360 degrees can give higher drag during strong parts of the stroke, andlower drag during weaker parts of the stroke.

Varying PWM duty cycles can be produced by a microprocessor arrangementas illustrated in FIG. 3C. The RPM of the power source and crank handleas well as its position can be read for example by sampling the voltageat a single generator phase as shown. And appropriate output voltagelevels can be sent to oscillators to generate PWM signals andenable/reset convertor chips as shown. Additionally, reading user inputand driving displays is also readily implemented as shown.

FIG. 3D illustrates a dual stage convertor with microprocessor control.The first stage is a buck stage that reduces the input generator voltageto a controlled lower value to charge a super cap or internal batterywell. The power is then passed to a SEPIC switching convertor thandrives loads above or below the intermediate stage voltage. It hassimilar capabilities of altering the crank drag torque when driven bydifferent duty cycles as seen in FIG. 3C.

FIG. 3D also illustrates that the control system can include anauxiliary electrical input that allows electrical energy from anadditional power source 333 to be inputted into the circuit shown,instead or in addition to the manually-driven generator power input.This would be useful if additional power sources such as a solar cellarray, car cigarette lighter, or other batteries of different voltageswere available. The system shown could then successfully convert theseother power sources to charge or drive a variety of output voltages andcurrents as already described for the generator.

FIG. 3E is a firmware flowchart that details the operation of thecircuit board. As cranking is initiated and voltage is produced, themicroprocessor comes alive and executes a sequence of steps toinitialize itself and reset the various convertor circuit chips. Apolling loop is then entered into which monitors crank rpm, position,and monitors load voltage and current, and looks for any user buttonpresses. The procedure computes and stores progress such as energydelivered so far, battery conditions such as temperature, etc. asearlier described. It also drives the display for all user information.

Additionally, human input torque capability is typically a function ofthe hand and arm position and direction of applied force, hence of crankangular position. The same is true of leg-driven devices. In oneembodiment, the control system adjusts the crank torque as a function ofcrank angle so that the drag is higher at the stronger arm positions andlower at the weaker arm positions as the crank is rotated through 360degrees. Essentially any profile of crank torque versus rpm or angle canbe readily implemented using this approach.

FIG. 3F is a simplified illustration of a power source 310 with thehousing 312 and the arm 354 of the crank assembly 314 at eight differentrotational positions. In FIG. 3F, the arm 354 in (i) the first position300A is at approximately 0 degrees, (ii) the second 300B is atapproximately 45 degrees, (iii) the third position 300C is atapproximately 90 degrees, (vi) the fourth position 300D is atapproximately 135 degrees, (v) the fifth position 300E is atapproximately 180 degrees, (vi) the sixth position 300F is atapproximately 225 degrees, (vii) in the seventh position 300G is atapproximately 270 degrees, and (viii) the eighth position 300H is atapproximately 315 degrees. It should be noted that the illustrations ofthe positions 300A-300H are for convenience of the reader and can bevaried.

In one embodiment, for example, (i) the torque experienced by the usercan be less at the first position 300A than the second position 300B,(ii) the torque experienced by the user can be less at the secondposition 300B than the third position 300C, (iii) the torque experiencedby the user can be more at the third position 300C than the fourthposition 300D, (iv) the torque experienced by the user can be more atthe fourth position 300D than the fifth position 300F, (v) the torqueexperienced by the user can be more at the fifth position 300F than thesixth position 300G, (vi) the torque experienced by the user can be moreat the sixth position 300F than the seventh position 300G, and (vii) thetorque experienced by the user can be more at the eighth position 300Hthan the seventh position 300G. In this example, the torque varies as afunction of position. At higher or lower speeds, the same behavior canbe implemented at a corresponding higher or lower torque level.

FIG. 3G is a graph that illustrates crank torque versus the armrotational position for a substantially constant rotational speed. FIG.3G illustrates that the torque experienced by the user varies accordingto the rotational position of the arm.

FIG. 3H is an alternate graph that illustrates crank torque versus thearm rotational position for a substantially constant rotational speedfor a different design. FIG. 3H also illustrates that the torqueexperienced by the user varies according to the rotational position ofthe arm.

For a substantially constant rotational speed, the difference betweenthe maximum crank torque experienced by the user at one rotationalposition and the minimum crank torque experience by the user at anotherrotational position can vary. For example for a substantially constantrotational speed, in alternative embodiments, the maximum crank torquecan be at least approximately 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50,55, 60, 65, 70, 80, 90, 100, 125, 150, 175, 200, 250, 300, 350, 400, or500 percent greater than the minimum crank torque experience by theuser.

For alternative example embodiments, a substantially constant rotationalspeed is within 5%, 10% or 20%.

Actively controlling the crank torque drag, as discussed above, can be ahighly desirable feature of the power source. For example, as the useris slowing down, the torque required to rotate the crank assembly isreduced. With this design, as rotational velocity decreases, cranktorque decreases. This can be desired because the user probably isslowing down because he/she is fatigued. Similarly, as cranking speed isincreased, the crank torque required to rotate the crank assembly israised. In this case, the user is probably speeding up since he/she isfeeling strong. This is superior to the typical commercially availablepower circuitry which maintain a constant wattage output. In thisundesirable, but typical case, as the user slows down, the dragincreases.

The relationship between the rotational velocity and the crank torquecan be varied to suit the design requirements of the power system. Forexample, in one embodiment a change of rotational velocity ofapproximately 5% results in a change in crank torque of approximately1%. Alternatively, (i) a change of rotational velocity of approximately10% results in a change in crank torque of approximately 10%; a changeof rotational velocity of approximately 15% results in a change in cranktorque of approximately 20%; and a change of rotational velocity ofapproximately 20% results in a change in crank torque of approximately50%.

Additionally, the user input 82 can allow the user to input desiredcrank torque drag for the convenience of the individual user. With thisdesign, power source 10 allows the user to maintain user comfort byallowing the user to set the cranking drag higher or lower for any speedat which they wish to operate. The battery charge rate is activelycontrolled so that the crank torque to the user is maintained asspecified irrespective of cranking speed. Stated another way, the chargerate is actively controlled to set a comfortable torque for rotating thecrank assembly 14. Different people have different desires for crankingtorques and speeds. This feature can be implemented via microprocessorcode in table lookup or formula fashion.

In an alternative embodiment, the power source is set to deliver aconstant battery current charging rate (constant power). This is easy toimplement, but results in crank drag that varies according to speed. Ifthe crank speed is lowered, the crank drag torque is increased to makethe charging power rate constant (power=torque×speed). Similarly, ascranking speed is increased, the crank torque is lowered to again makethe charging power rate constant.

In one embodiment, the control board must have power to begin operation,although the required power is very low. The circuits on the controlboard have features that can produce sufficient voltage to charge a capor supercap from a power off state with only human cranking and no cpuhelp. This is a unique power up feature. This can naturally be done withdiode rectifiers for BLDC generators. For SR generators, a small magnetnear the plurality of teeth of the rotor component producing modulatinge-m fields and a single coil driving a diode bridge can serve providethis unique power up feature.

Another embodiment for initially powering up the internal energy storagecomponent, a supercap in this example, is to briefly drive all generatedpower into the supercap. After the capacitor is charged (typically 1-3seconds), the control board will have sufficient power to turn oninternal circuitry and operate normally, now driving power to the outputbatteries being charged.

When the user input includes a certain power level, the control boarduses control loops to bring the system from power off to a known goodstate by slowly ramping up to the power requested by the user. Thisavoids trying to produce impossible output levels. In the case where alower output level can be accomplished with two distinct crank torquesat some fixed crank speed, the control board ensures that the lower,more efficient crank torque is always chosen.

Many of the features of the present invention are implemented bysuitable algorithms that are executed by the control board. For example,all voltages and, currents at critical circuit points, temperature,time, crank position and velocity are monitored by the softwareroutines.

In one embodiment, the control system automatically determines thepresence and power requirements of an unknown load attached to the powersource. For example, the flow source slowly ramps up the voltage untilit sees current flowing. The control board can then examine the voltageat this point and choose a suitable safe default charging rate for thedevice.

The control system receives the newly processed information from theuser input and transfers that information to power circuitry as data,and analog level, or PWM pulse train, ultimately to set the switchingwaveform of the power convertors through the second relay so that theoutput can be controlled to achieve the desired output power, etc.

During the operation of the power source 10, the control system monitorsthe output voltage and the current that are actually being generated. Athird data path transfers this information back to the control board.

The control board then transfers all input and output information to thedisplay through the fourth data path, so the user can monitor theprogress of the generation process. The display can provide status ofvarious input and output levels such as charging rate, chargingefficiency, joules delivered (gas gauge), output voltage, temperature,etc. It can use engineering units such as amps, coulombs, joules, volts,or user units such as cellphone talk time, hours of game play, percentfull, charging efficiency, etc. Additionally, moving graphic displayscan be employed to guide and pace users to the most ideal speeds andoffer motivational tools such as progress bars and other animations toreduce the boredom during longer charging operations.

Moreover, the control system can test for and display fault conditions,such as damaged batteries in the electronic device 11 (illustrated inFIG. 1A).

The plurality of sensors can be included to ensure that the power sourceis producing power as required to charge whatever mechanical device,through the battery pack, needs to be charged at that time. Theplurality of sensors can be arranged so that some of the plurality ofsensors are provided on the output load side and some of the pluralityof sensors are provided on the input generator side.

The output voltage, current, and temperature are measured at the outputside, or battery side. These are useful for monitoring battery-chargingconditions in order to keep voltages at proper levels and to avoidovercharge. Different battery chemistries have different chargingvoltage requirements and charge termination conditions. Tracking currentand voltage allows for safe charging and accurate determination of fullycharged state by known methods such as a specified end of chargevoltage, or negative ΔV when the voltage drops off by a specific amountnear full charge. Additionally, termination based on high cell voltagetemperature being reached is also implemented via the temperaturesensor.

There are also voltage and current sensors on the input side, thegenerator side, that are used by the control board for propercommutation of the coil phases. The crank torque (or drag) can bedirectly measured with a torque sensor such as a strain gauge oralternatively inferred by voltage and current measurements on thebattery terminals or the generator stator coil phases. One examplemethod is that in a BLDCM generator, the coil current is proportional tocrank torque (by constant Kt). The crank angle and rotation rate canalso be measured by an angular sensor such as 3 Hall devices or moresimply by counting phase voltage cycles as the poles pass by. Thisinformation is used for maintaining the crank torque as specified by theuser and also as a function of crank position.

FIG. 4 illustrates a view of another embodiment of the power source 410.In this embodiment, the power source 410 (Illustrated as a box) isembedded within an existing mobile electronic device 411 (illustrated asa box). In this embodiment, some of the components of the power source10 described above may not be necessary in the power source 410. Forexample, the user input 82, the display 80 and the control board 84 asdescribed above can be integrated into the user input 482, display 480,and the control board 484 of the electronic device 411.

As examples, the combined electronic device 411 can be portable and caninclude (i) communications devices such as mobile telephones, citizenband radios, family radio spectrum radio, and wireless internet devices,(ii) portable computing devices such as notebook computers, personaldigital assistants, and calculators, (iii) military electronic devices,such as night visions devices, communications devices, precision GPS,laser targeting devices, data displays, and computing devices, and (iv)other items such as digital cameras, camcorders, global positionsatellite devices, portable electronic games, flashlights, radios, andaudio CD/MP3 players. Alternatively, for example, the combinedelectronic device 411 can be stationary.

FIG. 5A illustrates another embodiment of power source 510 in a portableposition 502. In this embodiment, the power source 510 includes ahousing 512, a crank assembly 514 having a pair of pedals 508, and astand assembly 506 having a plurality of legs 509. In the portableposition 502, the pedals 508 and the legs 509 are folded against thehousing 512 to reduce the size of the power source 510. The power source510 can include components similar to the power source 10 illustrated inFIGS. 1A-1D.

FIG. 5B illustrates the power source of FIG. 5A in a use position 504.In this position, the distal ends of the legs 509 of the stand assembly506 are rotated away from the housing 512 and support the housing 512above the ground (not shown). Further, in the use position, the pedals508 are rotated away from the housing 512. The number of legs 509 can bevaried. For example, the stand assembly 506 can include three or fourlegs 509. Alternatively, the housing 512 could be designed to supportthe housing 512 in an upright position.

The pedals 508 are adapted to be engaged by the feet of the user. Thepedals 508 can go up and down or the pedals 508 can spin. Differentmethods exist to ensure that unidirectional rotation exists for the dualpedal 508 operated power source 510. In one embodiment, each pedal 508is adapted so that it pivots on an arm applying unidirectional rotation.A clutch can be used to ensure unidirectional rotation on each pedal508.

In another embodiment, a rack can be positioned under each pedal 508that engages a combination of gears and clutches on the arm to ensureunidirectional rotation. And a return spring can forcefully return thepedal to the upper position after it has been pressed fully to thebottom position in preparation for the next power stroke.

In yet another embodiment, the pedals 508 are once again adapted topivot on arms. In this embodiment, the pedals 508 can be designed sothat horizontal pedal surfaces push two cams that are rigidly mounted tothe arm. In this embodiment, the pedals operate 180 degrees out of phasedue to each cam mounting position. In still another embodiment of a dualpedal operated crank assembly, the pedals can be mounted on the arm oron a second arm with a transmission (belt, chain or idler gears) tocause the rotation of the gear assembly. FIG. 5C illustrates yet anotherembodiment of the power source 510C. In this embodiment, the pedals 508Coperate similar to a bicycle with no clutches involved in the operation.

In a dual pedal embodiment of this invention, the arm can be designed sothat the pivot assembly is substantially centrally located along thelength of the arm, and the arm extends away from the pivot assembly inopposite directions. In this embodiment, instead of a handle connectedat the distal end of the arm, pedals are connected at either end of thearm so that a force can be generated to rotate the arm about the pivotassembly in a manner similar to the motion of pedaling a bicycle.

In another embodiment of the present invention, the handle 56(illustrated in FIG. 1B) can be replaced with a pump. In thisembodiment, the pump is designed with a cylinder so that verticaldown-up strokes on the cylinder drive the arm through the use of aclutch. The pump method operates in a manner similar to that of anupright bicycle pump.

Alternatively, the crank assembly can be designed so that it can operatewith the handle or the pedals, i.e. the handle and pedals areinterchangeable. In this embodiment, the user can configure the crankassembly in the field by attaching the handle when a minimal size crankassembly is desired. When maximum power is desired, the user can easilyremove the handle and replace with the pedals for operation.

FIG. 6A is a perspective view of first embodiment of a power sourcecombination 600A and an electronic device 611A having features of thepresent invention. In this embodiment, the power source combination 600Aincludes a plurality of power sources 610A that are electricallyconnected together. In this embodiment, each power source 610A can havefeatures similar to the power source 10 described above and illustratedin FIG. 1A. The number of power sources 610A utilized in the powersource combination 600A can be varied. For example, in FIG. 6A, thepower source combination 600A includes three power sources 610A.Alternatively, the power source combination 600A can include more thanthree or less than three power sources 610A.

With this design two or more power sources 610 can cooperate to chargeone or more batteries of the electronic device 611. In one embodiment ofthe power source combination 600, each power sources 610 individuallyraises its output voltage until current starts to flow. The individualpower sources 610 monitor and regulate the current at the approximatelyconstant output voltage (set by load battery chemistry, temperature, andcharging conditions) and thereby control how many watts are delivered.One of the purposes of controlling the outputted watts from each powersources 610 is that this influences how much drag is felt by the userwho is operating the power sources 610, whether the crank assembly isoperated with the handle or the pedals. In this combination, informationcan be communicated back to each of the cooperating users as to whetherthe battery is nearing full charge, or is charging too fast. This can bemonitored through the use of a data line, thermocouples, or othersimilar monitoring devices.

In one embodiment of the power source combination 600, each powersources 610 is capable of delivering energy to the battery of theelectronic device 611 regardless of its voltage. So it is also possibleto hook the outputs of multiple power sources 610 in parallel to combinetheir energy and thus charge a battery more rapidly. A complication tothe power source combination 600 is that a battery charging too rapidlyneeds to be able to communicate this to the multiple power sources 610so that they slow down. This can be done via a battery-to-power source610 messages system as employed with smart batteries, or with a powersource 610 to power source system where a single power source 610assumes master control over the other slave power sources 610 andcommands their power output maximums. Communication between powersources 610 could be accomplished by placing signals over their joinedoutput power lines. The microprocessor in each slave power sources 610would receive the slow down commands from the master power sources 610and reduce power output to prevent battery damage the electronic device611 from overcharge.

FIG. 6B is a perspective view of a second embodiment of a power sourcecombination 600B and an electronic device 611B having features of thepresent invention. In this embodiment, the power source combination 600Bincludes a plurality of power sources 610B that are electricallyconnected together. In this embodiment, each power source 610B can havefeatures similar to the power source 510 described above and illustratedin FIGS. 5A and 5B. The number of power sources 610B utilized in thepower source combination 600B can be varied. For example, in FIG. 6B,the power source combination 600B includes three power sources 610B.Alternatively, the power source combination 600B can include more thanthree or less than three power sources 610B.

FIG. 6C is a perspective view of a third embodiment of a power sourcecombination 600C and an electronic device 611C having features of thepresent invention. In this embodiment, the power source combination 600Cincludes a plurality of power sources 61.0C that are electricallyconnected together. In this embodiment, the power source combination600C includes three power source 610C having features similar to thepower source 10 described above and illustrated in FIG. 1A and threepower sources 610C having features similar to the power source 510described above and illustrated in FIGS. 5A and 5B. The number of powersources 610C utilized in the power source combination 600C can bevaried.

FIG. 7A is a perspective view of another embodiment of a power source710 having features of the present invention. In this embodiment, thepower source 710 includes a housing 712, a crank assembly 714 and astand assembly 706 having a plurality of legs 709 that support thehousing 712 above the ground.

In this embodiment, the power source 710 is a foot-operated step chargerand the crank assembly 714 includes a first pedal 708A and a spacedapart secured pedal 708B. The pedals 708A, 708B are adapted to beengaged by the feet of the user. In this embodiment, the pedals 708A,708B are designed to move up in down in alternating fashion and thedownward stroke of the foot is the power stroke. Alternatively, thepedals 708A, 708B can be designed to spin similar to the arrangement ofFIG. 5C bicycle-style.

Alternatively, the crank assembly 714 can be designed for use withhandles (not shown). Alternatively, the handles and the pedals can beinterchangeable. In this embodiment, the user can configure the crankassembly 714 in the field by attaching the handles when a minimal sizecrank assembly is desired. When maximum power is desired, the user caneasily remove the handles and replace with the pedals for operation.

In one embodiment, the pedals 708A, 708B and the legs 709 can beselectively folded against the housing 712 to reduce the size of thepower source 710.

In this embodiment, each pedal 708A, 708B moves back and forth between afirst upper position 711A and a lower position 711B.

FIG. 7B is a partly exploded perspective view of the power source 710 ofFIG. 7A including the housing 712, the crank assembly 714, the gearassembly 716, the rotor component 718 including a rotor input 718A, thestator component 720, and the control system 724 (illustrated inphantom), that are somewhat similar to the corresponding componentsdescribed above. In this embodiment, the crank assembly 714 utilizespedals 708A, 708B that move up and down while causing unidirectionalrotation of the gear assembly 716 and the rotor component 718. Differentmethods can be used to ensure that unidirectional rotation exists forthe dual pedal 708A, 708B operated power source 710. In the embodimentillustrated in FIG. 7B, in addition to the pedals 708A, 708B, the crankassembly 714 includes a one-way drive mechanism, assembly 725 thatallows for unidirectional rotation of the gear assembly 716 and therotor component 718 and a returner assembly 727 that urges each of thepedals 708A, 708B upward.

In the embodiment illustrated in FIG. 7B, the one-way drive mechanismassembly 727 includes a first one-way mechanism 729A (illustrated inphantom) that is coupled with a first crank output 733A to the firstpedal 708A and a second one-way mechanism 729B that is coupled with asecond crank output 733B (illustrated in FIG. 7C) to the second pedal708B. Also, the returner assembly 727 includes a first returner 731Athat is coupled to the first pedal 708A and a second returner 731B(illustrated in FIG. 7D) that is coupled to the second pedal 708B.

FIGS. 7C-7E illustrate alternative perspective views of differentportions of the power source 710. In this embodiment, each returner731A, 731B is a resilient member, such as a coil spring that forcefullyreturns the respective pedal 708A, 708B to the upper position after ithas been pressed to the bottom position in preparation for the nextpower stroke. In this embodiment, each resilient member includes a firstend that is secured to the housing 712 and a second end that the coupledto the respective pedal 708A, 708B via the respective crank output 733A,733B. With this design, after the pedals 708A, 708B are forcefullypressed down by the user's feet, upon reaching the bottom position, theuser lifts his foot up and the returner 731A, 731B returns therespective pedal 708A, 708B to the top position.

FIG. 7F is a perspective view of the one-way mechanisms 729A, 729B andthe crank outputs 733A, 733B. In this embodiment, each one-way drivemechanism 729A, 729B is a clutch that couples the respective crankoutputs 733A, 733B and pedal 708A, 708B to the gear assembly 716. Theclutch allows the respective crank outputs 733A, 733B to engage the gearassembly 716 when rotated in one direction and to disengage the crankoutputs 733A, 733B from the gear assembly 716 when rotated in theopposite direction. A suitable clutch is a sprag type clutch.

This design allows for dual-leg operation by the user enabling balancedergonomics and maximum energy production.

In another embodiment, each one-way mechanism 729A, 729B can be acombination of gears and clutches that ensure unidirectional rotation.In one embodiment, the pedals 708A, 708B can be designed so thathorizontal pedal surfaces push two cams that are rigidly mounted to thearm. In this embodiment, the pedals operate 180 degrees out of phase dueto each cam mounting position. In still another embodiment of a dualpedal operated crank assembly, the pedals 708A, 708B can be mounted onthe arm or on a second arm with a transmission (chain or idler gears) tocause the rotation of the gear assembly 716. In this embodiment, thepedals 708A, 708B operate somewhat similar to a bicycle with no clutchesinvolved in the operation.

In the embodiment illustrated in FIGS. 7A-7F, the control system 724 canmake use of the same flexibility of the electronics architecturediscussed in connection with the power sources described above,including the ability to monitor crank angles, velocities and cranktorques, and voltages and currents at the generator inputs and loadbattery outputs.

In one embodiment, the control system 724 can have a number of importantdifferences. During operation of a handcranked power system, thecranking direction, torque and rpm of the crank and rotor isunidirectional and reasonably steady. This enables an efficientelectrical energy conversion circuit to be used because the somewhatconstant input voltages allow for circuit optimization around thelimited input voltage range. In contrast, a step powered power source710 receives drastically different torques depending on whether thepedals 708A, 708B are being forced downwards by the feet of theoperator, or returning back upwards with the clutch disengaged.Additionally, depending on the inertia and electrical drag on the rotorcomponent 718, the rpm and hence the output voltage of the power source710 can vary widely, making an efficient power conversion circuitdifficult to achieve.

In one embodiment, the control system 724 senses the pedal 708A, 708B(or other portion of crank assembly 714) positions and velocities(downwards or upwards), and rotor component 718 rotational speed anduses this information to modulate the load/battery charging rates (PWMduty cycle). During forceful pedal 708A, 708B downstrokes, the circuitwould set the circuitry to charge the battery rapidly, causing high dragtorque on the rotor component 718, to the pedals 708A, 708B and thecrank outputs 733A, 733B, and reducing the rpm speedup of the rotorcomponent 718. During the upstroke portion of the pedals 708A, 708B, thecircuit would quickly reduce the battery charging rate and thus inhibitrapid slowing down of the rpm of the rotor component 718 to a low speed.Preprogrammed waveforms would transition these duty cycles in a smooth,comfortable fashion for the user. The waveform would tailor the dragtorque to conform to the cycle of foot liftup, footfall in elevatedpedal position, full foot pressure downwards, and back to foot liftup.In this manner, the rpm of the rotor component 718 is kept in a greatlyreduced maximum-to-minimum speed range and thus output voltage range ofthe power source 710, allowing for higher efficiency energy conversioncircuitry to be used as in the case of the hand-cranked power source710.

Additionally, the control system 724 can control the rpm of the rotorcomponent 718 and control pedal 708A, 708B velocities so the user couldhave an adjustable comfortable stepping cadence, not too fast or tooslow. The “stair climbing” rate could be adjusted by the user byinterfacing with the control system 724 to be faster or slower. Also,the adjustable drag method used by the control system 724 allows a lowstep-up gear ratio mechanism to behave similar to high step-up gearratio mechanisms—largely at constant speed with operator steppingactions. In some embodiments, lower gear ratios are desirable becausethey have fewer frictional losses than high gear ratio mechanisms. Itwould have none of the drastic speedups and slowdowns that plague lowgear ratio generators where the power down stroke happens too quicklyand the user cannot bring his full weight (and power generatingcapability) to bear before the pedal comes to the bottom position. Inone embodiment, the user would feel as though he were climbing astaircase at largely constant speed (faster or slower as desired).

In one embodiment, the goal of the charging electronics (the controlsystem) that take the voltage/current from the stepping power source710, make decisions based upon input from multiple factors to providethe load or battery with the optimal power that give a pleasant usageprofile of the human user. The control system monitors temperature,revolutions per second, the voltage, and current over time to computethe torque within the generator and amount of charge delivered. Thecontrol system provides a load profile to optimize shaft speed andtorque which ultimately is reflected in the petals 708A, 708B of thepower source 710. This system allows the user to feel a virtual flywheeleffect and gives a normal feeling of feedback.

In one embodiment, the power source 710 receives the electrical energyand electronically controls the amount of torque required to rotate therotor input 718A by dynamically adjusting the level of the outputvoltage to the load, the output current to the load, and/or the level ofthe electrical energy delivered to a load. In this embodiment, forexample, the control system 724 electronically controls the amount oftorque required to rotate the rotor input 718A and/or each crank output733A, 733B. As an example, when the first pedal 708A is in the firstupper position 711A, the torque required to rotate the first crankoutput 733A is greater (e.g. 1, 2, 3, 5, 10, 20, 30, 40, 50, 60, 70, 80,or 90%) than the torque required to rotate the first crank output 733Awhen the first pedal 708A is at the second lower position 711B.

In one embodiment, the control system 724 electronically controls therotational velocity of the rotor component 718 so that the rotationalvelocity is approximately constant during the movement of each pedal708A, 708B back and forth between the first position 711A and the secondposition 711B. As provided herein, in alternative embodiments,approximately constant can mean varying in speed by less thanapproximately 1, 10, 25, 50, 75 percent.

FIG. 8A is a graph that illustrates capacitive (leading) and inductive(lagging) current for one embodiment of a typical signal phase constantspeed power source.

The impedances (in Ohms) are:

-   -   a) Resistance (R)    -   b) Inductive reactance X_(L)=ωL    -   c) Capacitive reactance $X_{C} = \frac{1}{\omega\quad C}$

FIG. 8B is an electrical diagram that facilitates the Impedancecalculation.

The impedance of a resistance and a reactance connected in series is:

-   -   Z={square root}{square root over (R²X²)}. The phase angle is:        Ø=a tan X.

To generate an accurate understanding of the torque waveforms that thecharging electronics will see as an input, we must take the simplesingle phase waveform above and modify it to include a torque profile atypical user may apply in a walking and running state as shown below.

FIG. 8C is a graph that illustrates shaft torque profile for oneembodiment of a power source.

The charging electronics takes this input and adjusts the output power(Voltage*Current) with methods such as PWM control of a charge into abattery. This can be considered as a variable charge rate into a loadand by adjusting this charge rate the torque on the shaft can be alteredproportionally, thus by letting the “charge electronics” change thecharge rate on the load you can free up the shaft to spin at nearlyconstant speed through areas of low input torque as though a highinertia flywheel were attached to the rotor component 718. This abilityto generate nearly constant rotor 718 velocity irrespective of inputshaft torque simulates the effect of a having high inertia flywheel orhigh step-up gear ratio being present in the system. It results incomfortable operation by the user. With this embodiment, the added sizeand weight of an actual flywheel, or the high friction levels from ahigh ratio gear train will not be present. Also, selecting differenttarget rotor speeds would allow the user to adjust the effort levels.

Given known phase and voltage relationships of the input waveform, themethod of sensor and control of the charge electronics can be done withand not limited to microprocessor tracking of the input voltage from thegenerator and PWM control of the load.

Shown herein is an example of a PWM control of a single phase circuitthat adjusts the Bipolar circuit of field effect transistors (FET) ontime to achieve a desired load current.

FIG. 8D is a graph that illustrates current, voltage waveforms inbipolar operation of a single phase bridge rectifier with pulse widthmodulation.

Once we combine all the FET PWM outputs with the input waveform we cannow visualize the closed loop control illustrated in FIG. 8E. Morespecifically, FIG. 8E is a graph that illustrates shaft torque profilefor another embodiment of a power source.

The method of using PWM to control charge rate does depend on a constantsink source. If the load is not a true sink, for example, a 1K OHMresistor which may look like a full battery, the “on” state of the PWMwill not source much current and the user will not feel resistance. Tosolve this issue we applied a calculated resistive load in addition tothe battery. This resistive load is calculated from the input andmeasured sensor data within the microprocessor. The resistive load canbe, but not limited to, a series of resistors controlled by FET or aSink transistor circuit. With this we can have the same load resistancefor all levels of storage capacity of the batteries, thus allowing thePWM to act as the closed loop control.

In one embodiment, the control system includes an energy dissipater thatselectively dissipates excess energy. Stated another way, the controlsystem can provide a way to selectively and accurately generate drag onthe crank assembly in one or more of the power sources described above.More specifically, FIGS. 9A-9C each illustrate an alternative embodimentof a circuit diagram that can be used in the control system. Each ofthese embodiments includes an additional feature of adding an internalshunt resistor meant to dissipate excess energy. The shunt resistor canbe of a fixed value, alternatively it simply can be a short circuit(resistance equals zero), utilizing the resistance of the generatorwindings. This is so if the battery is charging too fast and the circuitwants to stop putting in all that electricity, it doesn't just stop andthereby reduce the torque on the pedal of the crank assembly to zero anddropping the user to the floor. Instead, it the control systemcontrollably and selectively diverts the electricity into the internalshunt resistor to dump the energy as heat, and still retain someresistance on the pedal to the user. In the case of a zero ohm shuntresistance, the energy would be dissipated as heat primarily in thestator windings. Various control implementations of this internal energyshunt are possible. In the embodiments illustrated, each circuitincludes a shunt resistor 901A, 901B, 901C and a switch 903A, 903B, 903Cthat actively controls the current to the respective shunt resistor901A, 901B, 901C. One possible method is shown in FIG. 9B. In thisembodiment, the internal shunt 901B is placed in parallel with theconverter circuitry, with a pulse width modulated micro-controlledswitch 903B actively controlling the amount of energy diverted to theresistor 901B. Another method is to implement the SPDT switch 903A ofFIG. 9A with PWM switched FETs as shown in FIG. 9C. This is not arequired addition to the unit, but a possibly useful addition. At somepoint, the user should slow down his charging rate, save his effort.

Additionally, the control system can cause one or more signals orinformation to be transmitted to the user through the crank assembly.Stated another way, an additional unique feature of the currentinvention is to allow the creation of vibrations and pulses into thefoot pedals or hand crank as the power source is being operated totransfer one or more signals to the user. A way to do this would be tohave the control system abruptly change the charging rate to the loadfor an interval of time, and then returning to the previous chargingrate. The user would feel a “pulse” through their hands or feet.Alternatively, for example, the control system can transfer current to aseparate motor that vibrates the housing and/or crank assembly.

The vibration and/or pulses can be used to convey information or signalsto the user such as charging progress, charging complete, optimalcranking speeds, slowdown cranking, speed up cranking, or informationthat would be displayed by the display 80. This information can be codedas pulses to be felt by the user. The advantage of this method is thatthe user need not have a clear view of the display in order to stillreceive information. This would be especially advantageous in the footoperated unit where the users eyes are several feet away from the datadisplay on the device. The time interval can vary according to the typeof information being transferred. For example, the time interval can bealternatively 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 1, 1.5, 2, 3, or 5seconds.

As provided herein, a first type of information can be transferred witha first signal and a second type of information can be transferred witha second signal. As an example, the first signal can be one or morepulses at a first time interval and the second signal can be one or morepulses at a second time interval that is different than the first timeinterval.

Stated another way, the control system can cause the crank assembly tovibrate at a first pulse to transfer the first signal to the user andcan cause the crank assembly to vibrate at a second pulse to transfer asecond signal to the user, the second pulse being different than thefirst pulse. As provided herein, the control system can cause a torqueof the crank assembly to change at a first rate to transfer a firstsignal to the user and can cause the torque of the crank assembly tochange at a second rate to transfer a second signal to the user.

While the particular power sources as shown and disclosed herein isfully capable of obtaining the objects and providing the advantagesherein before stated, it is to be understood that it is merelyillustrative of the presently preferred embodiments of the invention andthat no limitations are intended to the details of construction ordesign herein shown other than as described in the appended claims.

1. A power source that is powered by a user to charge a load, the powersource comprising: a housing; a stator component secured to the housing;a rotor component that rotates relative to the stator component, whereinrotation of the rotor component relative to the stator component resultsin the generation of electrical energy; a crank assembly that includes afirst crank output that is rotated by the user, wherein rotation of thefirst crank output results in rotation of the rotor component; and acontrol system that receives the electrical energy and electronicallycontrols the amount of torque required to rotate the rotor componentbased on at least one of (i) an angular velocity of the first crankoutput, (ii) an angular position of the crank assembly, (iii) a currentin the load, and (iv) a current generated by rotation of the rotorcomponent relative to the stator component.
 2. The power source of claim1 wherein the control system includes an additional electrical input forreceiving electrical energy from an additional power source.
 3. Thepower source of claim 1 wherein the control system causes a first signalto be transmitted to the user through the crank assembly.
 4. The powersource of claim 3 wherein the control system causes the crank assemblyto vibrate to transfer the first signal to the user.
 5. The power sourceof claim 4 wherein the control system causes the crank assembly tovibrate at a first pulse to transfer the first signal to the user. 6.The power source of claim 5 wherein the control system causes the crankassembly to vibrate at a second pulse to transfer a second signal to theuser, the second pulse being different than the first pulse.
 7. Thepower source of claim 3 wherein the control system causes the torquerequired to rotate the rotor component to change at a first rate totransfer a first signal to the user.
 8. The power source of claim 7wherein the control system causes the torque required to rotate therotor component to change at a second rate to transfer a second signalto the user.
 9. The power source of claim 1 wherein the control systemincluding an energy dissipater that selectively dissipates energy.
 10. Apower source that is powered by a user to direct current to an object,the power source comprising: a housing; a stator component secured tothe housing; a rotor component that rotates relative to the statorcomponent; a crank assembly that is coupled to the rotor component, thecrank assembly including a first crank output that rotates relative tothe housing, wherein rotation of the first crank output by the userresults in rotation of the rotor component relative to the statorcomponent and the production of electrical energy; and a control systemthat receives the electrical energy and causes a first signal to betransmitted to the user through the crank assembly.
 11. The power sourceof claim 10 wherein the control system causes the crank assembly tovibrate to transfer the first signal to the user.
 12. The power sourceof claim 11 wherein the control system causes the crank assembly tovibrate at a first pulse to transfer the first signal to the user. 13.The power source of claim 12 wherein the control system causes the crankassembly to vibrate at a second pulse to transfer a second signal to theuser, the second pulse being different than the first pulse.
 14. Thepower source of claim 10 wherein the control system causes a torquerequired to rotate the rotor component to change at a first rate totransfer a first signal to the user.
 15. The power source of claim 14wherein the control system causes the torque required to rotate therotor component to change at a second rate to transfer a second signalto the user.
 16. The power source of claim 10 wherein the control systemincludes an energy dissipater that selectively dissipates energy.
 17. Apower source that is powered by a user to direct current to an object,the power source comprising: a housing; a stator component secured tothe housing; a rotor component that rotates relative to the statorcomponent; a crank assembly that is coupled to the rotor component, thecrank assembly rotating relative to the housing, wherein rotation of thecrank assembly by the user results in rotation of the rotor componentrelative to the stator component and the production of electricalenergy; and a control system that receives the electrical energy, thecontrol system including an energy dissipater that selectivelydissipates electrical energy.
 18. The power source of claim 17 whereinthe control system selectively dissipates electrical energy when theobject is charged.
 19. The power source of claim 17 wherein the controlsystem causes a first signal to be transferred to the user through thecrank assembly.
 20. The power source of claim 17 wherein the controlsystem dynamically adjusts the level of at least one of an outputvoltage and an output current.